Question

Which of the following is water-soluble?
A. Phycobilin
B. Carotene
C. Xanthophyll
D. Chlorophyll

Answer 1

Hint: Pigments are the colored substances that give color to the various parts of the plants. Apart from imparting color to organs some pigments also perform specific metabolic functions. Moreover, pigments are classified into two classes, namely water-soluble and fat-soluble. Water-soluble pigments are those pigments that can be dissolved in water.

Complete answer: -Phycobilin is a class of hot water-soluble pigments. Phycobilins consist of two kinds of pigments. These two types of pigments are Phycocyanin and Phycoerythrin. Phycobilins are concerned with the harvesting of light energy. They transfer the solar energy to the chlorophyll molecules.
-Carotene is the orange or red-colored pigment. They are a class of the Carotenoid pigments. Carotenoids are fat-soluble pigments. Carotenoids are known as the secondary or shield pigments as they protect the chlorophyll molecules from photo-oxidation and solarization.
-Xanthophyll is the yellow-colored pigment. They are a class of the Carotenoid pigments. Carotenoids are fat-soluble pigments. Carotenoids are known as the secondary or shield pigments as they protect the chlorophyll molecules from photo-oxidation and solarization.
-Chlorophyll is a green-colored pigment. They are the main or primary pigment. Chlorophyll is a fat-soluble pigment. It is directly involved in the process of light reaction of photosynthesis. Thus, based on the above information we can conclude that Phycobilin is a water-soluble pigment.
Hence, the correct answer is option (A).

Note: Phycocyanin is the blue-colored pigment. They are only present in cyanobacteria. They are of two types namely c-phycocyanin and r-phycocyanin, where c-phycocyanin is dominant. On the other hand, phycoerythrin is the red-colored pigment. They are found in red algae. They are also of two types namely c-phycoerythrin and r-phycoerythrin, where r-phycoerythrin is dominant.